Update nixpkgs
All tests are green:
nix-build -A tests
/nix/store/7zc7jmgr8znpvwsd28p5bd8f41rjlkyn-vm-test-run-test-auto-upgrade
/nix/store/c4b1vgpv672bnw57bx2p19yqm9nfnq5p-vm-test-run-test-backup
/nix/store/wn5qx5l1q7gi4zn6dqh0s3yjdfayp59y-vm-test-run-test-full
/nix/store/mfmn0hzwdz2qysgkjzfgjmq85kcry6qx-vm-test-run-test-keys
/nix/store/vz6h7fba1z474a2gyk9m82lr449ab8yd-vm-test-run-test-mail
/nix/store/l6nybf1hic3svawmvmdsmas17d9gi8j0-vm-test-run-test-nextcloud
/nix/store/m87f7w3gg0axilpa97579cmajbd41xb7-vm-test-run-test-prometheus
/nix/store/5rfnfy5qkhvh059v3yxglmkvj11lk81h-vm-test-run-test-vpn